cholestyramine vs dutasteride/tamsulosin

PlainMeds reviewed this comparison against our methodology in August 2026. It places FDA and CMS record fields side by side, without recommending either medication.

Side-by-side comparison of cholestyramine and dutasteride/tamsulosin. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.

minor Known Drug Interaction

7.7 Cholestyramine Dutasteride Administration of a single 5 mg dose of dutasteride followed 1 hour later by a 12 g dose of cholestyramine does not affect the relative bioavailability of dutasteride [see Clinical Pharmacology ( 12.3 ) ] .

Drug Class
cholestyramine Bile Acid Sequestrant
dutasteride/tamsulosin 5-ARI / Alpha-Blocker Combination
Type
cholestyramine Prescription
dutasteride/tamsulosin Prescription
Summary
cholestyramine

Cholestyramine is a medicine that helps lower high cholesterol levels in your blood. It works by preventing your body from absorbing cholesterol in the intestines.

dutasteride/tamsulosin

This medicine combines two drugs to treat enlarged prostate in men. It helps improve urine flow and reduce symptoms.

What It Treats
cholestyramine

This medicine is used with a diet to lower high cholesterol, especially LDL cholesterol (the "bad" cholesterol). It may also help if you have high triglycerides, but it's not the best choice if high triglycerides are your main problem. Lowering cholesterol helps reduce your risk of heart disease.

dutasteride/tamsulosin

This medicine treats benign prostatic hyperplasia (BPH), also known as enlarged prostate, in men. It helps to relieve symptoms like frequent urination, difficulty starting urination, and weak urine stream. This medicine is not approved to prevent prostate cancer.

How It Works
cholestyramine

Cholestyramine is a resin that binds to bile acids in your intestines. Bile acids help digest fats, including cholesterol. By binding to bile acids, cholestyramine prevents them from being reabsorbed, so your body uses cholesterol to make more bile acids, which lowers cholesterol levels in your blood.

dutasteride/tamsulosin

This medicine contains two drugs that work in different ways. Dutasteride lowers a hormone called DHT that causes the prostate to grow. Tamsulosin relaxes the muscles in the prostate and bladder, making it easier to urinate.

Common Side Effects
cholestyramine
  • Constipation
dutasteride/tamsulosin
  • Problems with ejaculation
  • Impotence (trouble getting or keeping an erection)
  • Decreased sex drive
  • Dizziness
  • Breast enlargement or tenderness
FAERS Reports
cholestyramine
  • Diarrhoea 1,631
  • Fatigue 877
  • Nausea 783
  • Arthralgia 621
  • Headache 543
dutasteride/tamsulosin
  • Shortness of breath 1,233
  • Tiredness 1,142
  • Feeling lightheaded or unsteady 986
  • Weakness 933
  • Loose stools 897
Serious Warnings
cholestyramine

Since cholestyramine can affect how your body absorbs other medicines, take other drugs at least 1 hour before or 4 to 6 hours after taking cholestyramine.

dutasteride/tamsulosin

This medicine can cause dizziness, lightheadedness, and fainting, especially when you stand up. Be careful to avoid falls or injuries. Do not take this medicine with other alpha-blockers, as it can lower your blood pressure too much. This medicine can affect your PSA levels, which are used to screen for prostate cancer, so tell your doctor you are taking this medicine. Pregnant women should not handle this medicine, as it can harm a male fetus.

Pregnancy
cholestyramine

Tell your doctor if you are pregnant or plan to become pregnant. Cholestyramine may affect how you absorb vitamins, so your doctor may recommend supplements. Talk to your doctor about the risks and benefits of taking this medicine while breastfeeding.

dutasteride/tamsulosin

This medicine is not for women. It can harm a male fetus if a pregnant woman is exposed to it. Pregnant women should not handle this medicine.

Also Compare, Nearby Drugs

Compare cholestyramine with

How to Read This cholestyramine vs dutasteride/tamsulosin Comparison

cholestyramine is classified in the Bile Acid Sequestrant drug class, while dutasteride/tamsulosin sits within the 5-ARI / Alpha-Blocker Combination class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are prescription-only, so a licensed provider must authorize use.

Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, cholestyramine has 4,455 submissions while dutasteride/tamsulosin has 5,191. Those figures reflect cumulative reporting volume, not per-patient risk, so older, widely dispensed drugs typically look worse on count alone. These two drugs have a known minor interaction flagged in FDA labeling, attributed to cholestyramine does not stop the body from absorbing dutasteride, even when taken shortly after a dose.. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.

A table cannot represent individual circumstances. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This registry does not provide medical, treatment, substitution, or medication-change directions for cholestyramine or dutasteride/tamsulosin.

Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.